What’s in a Name? Biosimilar Nonproprietary Names

June 17, 2019
By Noel Courage

The U.S. federal government created a specially-designed, abbreviated biosimilar approval pathway. The Biologics Price Competition and Innovation Act (“BPCIA”) was part of the Patient Protection and Affordable Care Act (a/k/a “ObamaCare”) (H.R. 3590, 111th Congress, 2010) and created the regulatory process by which competitive versions of a previously-licensed biological product could be brought to market (see § 7002). Prior to the BPCIA system, certain biosimilar manufacturers could attempt to obtain biosimilar approvals through section 505(b)(2) of the Federal Food, Drug, and Cosmetic Act or a standard new biologic license application (BLA) (Public Health Service Act – Regulation of Biological Products, Section 351). These avenues are still open, but the BPCIA is expected to become the primary process for biosimilar approval.

As amended, section 351(i) of the Public Health Service (PHS) Act defines biosimilarity to mean “that the biological product is highly similar to the reference product notwithstanding minor differences in clinically inactive components” and that “there are no clinically meaningful differences between the biological product and the reference product in terms of the safety, purity, and potency of the product.” It was not until March 2015, that the first biosimilar, Sandoz’s filgrastim (Zarxio), was approved in the U.S. by the BPCIA pathway. The product did not launch, however, until September, 2015 as a result of litigation with Amgen. The FDA assigned the product the temporary generic name “filgrastim-sndz.” note the “-sndz” suffix on the end of the typical nonproprietary name “filgrastim.” The FDA took several years to develop its written policies on biosimilar naming. In 2015, the FDA issued a draft guidance on the naming of biosimilars (U.S. FDA, 2015a). The FDA finalized its guidance in January 2017 (“Nonproprietary Naming of Biological Products”). The FDA again stated that it intended to use an arbitrary, four-letter suffix on the names of biosimilars to distinguish them from their reference product counterparts. This is in contrast to Europe and Canada, where no prefix was required – the biosimilar product went by the same name as the branded product. This is a significant commercial and regulatory issue in that the prefix, at first impression, emphasizes the biosimilar product as being a different product than the original brand. The FDA sees a benefit in its approach to try to ensure safer dispensing practices and pharmacovigilance.

The FDA recently released an updated revised draft guidance document on naming, which is available for public comment until May 7, 2019. First, the FDA is not going to go back and add a suffix to modify the names of biological products licensed under the old systems before the BPCIA. On this issue, the FDA says it is leaving well enough alone. The FDA is also considering whether to include vaccines in the naming guidance, as the current practices in place to differentiate vaccines may be sufficient. Another hot topic is naming of interchangeable biologic drugs and biosimilars. Most biosimilars are not currently considered interchangeable. The FDA does intend to use a unique distinguishing suffix. The applicant for the proposed interchangeable product would propose the suffix. The draft guidance is for comment purposes only, so stakeholders with an interest should promptly provide their input to make their points known.



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